Security during transportation of freight is an important consideration. It is known to secure ISO freight containers with security seals but these do not provide the security that might be desired.
ISO freight containers and other cargo may pass through the control of many different parties. However, responsibility of for the contents of the freight container lies with the party that sealed that container. Accordingly, that party sealing the container needs to be confident that the container, or other cargo, cannot be accessed. Current security seals do not give this level of knowledge. Thus, a market has developed for secondary security devices that can be fitted for the whole or part of a journey to add further security.
If a security device is to be used for only a portion of the cargo's journey then it may need to be fitted to a freight container that has already been sealed with an ISO seal. Some prior art security devices, such as WO2008/017841, uses apertures intended for security seals and accordingly is not suitable for securing a freight container or other cargo for only part of its journey.
Typically prior art devices, including that shown in U.S. Pat. No. 5,775,747, try to physically prevent opening of a container, such as an ISO freight container, to which they are fitted. Trying to prevent opening does not provide the confidence needed that the contents of a freight container to which the device has been fitted have not been accessed. Parties involved in nefarious activity have developed a significant array of techniques to gain access to containers without the need to operate the operating bars, etc. or to remove locks and refit them.
It can also be a problem to recover a security device that has been used to secure a freight container or other cargo since the security device will finish its journey somewhere remote from where it needs to be used again.